A population-based case-control study of epithelial ovarian cancer, which will investigate the association between genital talc use, infertility, infertility treatments, hormone use, oral contraceptive use, gynecologic operations, nutritional factors and physical activity and the development of epithelial ovarian cancer is proposed. The study will be performed in the multi-ethnic, multi-racial community of Cook County, Illinois. Approximately 750 incident epithelial ovarian cancer cases occurring in this community will be ascertained over a three year period. Histologic specimens obtained during diagnostic operation of the case will be evaluated by the study pathologist to consistently classify histologic subtype and degree of malignancy. Approximately 1500 population controls, matched on age and race, will be ascertained using random digit dialing (less than age 65) and lists of medicare recipients maintained by the Health Care Financing Administration (age 65 or higher). Etiologic information will be ascertained using a self-administered food-frequency questionnaire and an in-person interview. Analyses will be performed using conditional logistic regression and polychotomous logistic regression.